CN113196157A

CN113196157A - Display device and manufacturing method thereof

Info

Publication number: CN113196157A
Application number: CN201980002678.4A
Authority: CN
Inventors: 黄华
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2021-07-30
Anticipated expiration: 2039-11-29
Also published as: WO2021102920A1; US11874552B2; CN113196157B; US20230161191A1

Abstract

A display device and a method for manufacturing the same are provided. The manufacturing method of the display device comprises the following steps: sequentially stacking a first substrate (100), a second substrate (200) and a third substrate (300) to form a liquid crystal display panel and a dimming panel, wherein the liquid crystal display panel comprises the first substrate (100) and the second substrate (200), and the dimming panel comprises the second substrate (200) and the third substrate (300); a first polarizer (600) is formed on the third substrate (300) on the side away from the second substrate (300). The first polarizer (600) comprises a first metal wire grid polarizer (610) and a transparent protection layer positioned on one side of the first metal wire grid polarizer (610) far away from the third substrate (300). The first metal wire grid polarizer is used as a reflection-type polarizer, so that the light transmittance of the dimming panel can be improved; the transparent protective layer is used as a protective layer in the process manufacturing process and the final product, so that the thickness of the display device is reduced, and the light efficiency utilization rate can be increased.

Description

Display device and manufacturing method thereof

Technical Field

At least one embodiment of the present disclosure relates to a display device and a method of fabricating the same.

Background

For the display liquid crystal panel, the display image quality of the display panel can be improved by combining Local Dimming (LD). The local dynamic backlight technology can reduce power consumption to a great extent, improve imaging contrast, increase gray scale number, reduce ghost shadow and the like.

Disclosure of Invention

At least one embodiment of the present disclosure provides a method for manufacturing a display device, including: stacking a first substrate, a second substrate, and a third substrate to form a liquid crystal display panel and a dimming panel, the liquid crystal display panel including the first substrate, the second substrate, and a display liquid crystal layer between the first substrate and the second substrate, the dimming panel including the second substrate, the third substrate, and a dimming liquid crystal layer between the second substrate and the third substrate; and forming a first polarizer on one side of the third substrate far away from the second substrate. The first polaroid comprises a first metal wire grid polaroid and a transparent protective layer which are sequentially stacked, and the transparent protective layer is located on one side of the third substrate, away from the first metal wire grid polaroid.

For example, before the first polarizer is formed on the side of the third substrate away from the second substrate, the method includes: forming a dimming cell array on one side of the third substrate; the aligning of the side of the third substrate, on which the dimming cell array is formed, with the second substrate to form the dimming panel, and the forming of the first polarizer on the side of the third substrate, which is away from the second substrate, includes: and forming the first polaroid, and transferring and attaching the first polaroid to one side of the third substrate, which is far away from the second substrate.

For example, forming the first polarizer includes: sequentially forming a mechanical stripping layer, the transparent protective layer, the first metal wire grid polarizer, a bonding protective layer and a storage protective layer which are arranged in a laminated manner on a bearing substrate; transferring and attaching the first polarizer to one side of the third substrate far away from the second substrate comprises the following steps: and after removing the mechanical stripping layer, the bearing substrate and the storage protective layer, attaching one side of the attaching protective layer, which is far away from the first metal wire grid polarizer, to the third substrate.

For example, forming the first polarizer on a side of the third substrate away from the second substrate includes: the first metal wire grid polarizer and the transparent protective layer which are laminated are sequentially formed on one side of the third substrate to form the first polarizer, and the method comprises the following steps after the first polarizer is formed on one side of the third substrate, which is far away from the second substrate: forming a dimming cell array on the other side of the third substrate, wherein the process temperature for forming the dimming cell array is not more than 350 ℃; and aligning the third substrate with the side of the dimming cell array and the second substrate to form the dimming panel.

For example, the transparent protection layer comprises a first transparent protection layer in contact with the first metal wire grid polarizer, and a second transparent protection layer positioned on one side of the first transparent protection layer far away from the first metal wire grid polarizer.

For example, the material of the second transparent protection layer is colorless polyimide, the transparency of the second transparent protection layer is greater than 90%, the yellow index is less than 5, the thickness is less than 5 micrometers, and the second transparent protection layer is configured as a back film of the dimming panel.

For example, before forming the liquid crystal display panel, the method includes: forming a second polarizer on one side of the second substrate; after the second polarizer is formed, forming a display unit array on the other side of the second substrate, wherein forming the liquid crystal display panel includes: and aligning one side of the second substrate, on which the display unit array is formed, with the first substrate.

For example, forming the second polarizer includes sequentially forming a second metal wire grid polarizer, a third transparent protective layer, a fourth transparent protective layer, and a temporary protective layer on the second substrate; the step of aligning the side of the second substrate on which the display unit array is formed with the first substrate includes: removing the temporary protection layer; and the side of the second substrate, on which the second polarizer is formed, is paired with the third substrate to form the dimming panel.

For example, the third transparent protective layer is made of silicon oxide, and the thickness of the third transparent protective layer is 1000-2000 angstroms; the fourth transparent protection layer is made of amorphous silicon, and the thickness of the fourth transparent protection layer is 60-100 angstroms.

At least one embodiment of the present disclosure provides a display device including: a first substrate; a second substrate configured to be aligned with the first substrate to form a liquid crystal display panel; a third substrate configured to be aligned with the second substrate to form a dimming panel; and the first polaroid is positioned on one side of the third substrate, which is far away from the second substrate. The first polaroid comprises a first metal wire grid polaroid and a transparent protective layer which are sequentially stacked, and the transparent protective layer is located on one side of the third substrate, away from the first metal wire grid polaroid.

For example, the first polarizer further includes a bonding protection layer located on one side of the first metal wire grid polarizer facing the third substrate, and one side of the bonding protection layer away from the first metal wire grid polarizer is bonded on the third substrate.

For example, a second polarizer is disposed on a side of the second substrate facing the third substrate, the second polarizer includes a second metal wire grid polarizer, a third transparent protective layer and a fourth transparent protective layer sequentially disposed on the second substrate, and the second metal wire grid polarizer is disposed between the third transparent protective layer and the second substrate.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description relate only to some embodiments of the present disclosure and are not limiting to the present disclosure.

Fig. 1 is a partial structural schematic diagram of a display device provided according to an example of an embodiment of the present disclosure;

FIGS. 2-4 are schematic diagrams illustrating a process of forming a first polarizer in an example of an embodiment of the present disclosure;

fig. 5 to 6 are schematic views illustrating the formation of a first polarizer on a third substrate according to another example of an embodiment of the present disclosure;

fig. 7 is a schematic view of a second polarizer formed on a second substrate according to another example of the present disclosure;

FIG. 8 is a schematic diagram of an array of display cells formed in the example of FIG. 7;

fig. 9 is a schematic view of the side of the second substrate on which the display cell array is formed and the first substrate being aligned with each other;

FIG. 10 is a schematic structural diagram after the temporary protection layer is removed;

fig. 11 is a schematic structural diagram of a dimming panel formed by cell-pairing the second substrate in the liquid crystal display panel shown in fig. 10 and the third substrate in the example shown in fig. 6.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items.

In order to improve the Contrast of the lcd, the backlight emitted from the backlight module is usually controlled in a partitioned manner, and the intensity of the backlight in different areas is dynamically adjusted according to the gray scale requirement of the display frame, so as to achieve a High Dynamic Contrast (HDR). The backlight module capable of dynamically dimming can be divided into a side-in type backlight module and a direct type backlight module; the lateral backlight module can only perform partition control in the row direction or the column direction, that is, only one-dimensional dynamic dimming can be realized, so that the effect of dynamic contrast is not ideal; while the direct-type backlight module can realize two-dimensional dynamic dimming through the light emitting elements arranged in a matrix, in order to prevent Mura defects, the light mixing distance from the light emitting elements to the display panel needs to be set large, so that the backlight module has large thickness and is difficult to realize lightness and thinness.

In order to improve the contrast of the liquid crystal display device and realize the light and thin design, the liquid crystal display device can adopt a double-liquid-crystal-box structure, one liquid crystal box is used for carrying out partition dynamic adjustment on backlight, and the other liquid crystal box is used for displaying pictures normally. The liquid crystal display device adopting the double-liquid-crystal-box structure can realize the partition dynamic adjustment of the pixel level by dynamically adjusting the backlight in a partition mode through the liquid crystal box, thereby realizing high dynamic contrast. However, two liquid crystal cells generally include four display substrates, and therefore, when the two liquid crystal cells are overlapped, the light transmittance is easily reduced, so that the overall light efficiency of the liquid crystal display device is reduced. Moreover, the double-layer liquid crystal box structure can have the technical problems of rainbow lines, water ripples, mole lines and the like in the preparation process, and the market demand of high-end products is difficult to meet.

The embodiment of the disclosure provides a display device and a manufacturing method thereof. The manufacturing method of the display device comprises the following steps: stacking a first substrate, a second substrate and a third substrate to form a liquid crystal display panel and a dimming panel, wherein the liquid crystal display panel comprises the first substrate, the second substrate and a display liquid crystal layer positioned between the first substrate and the second substrate, and the dimming panel comprises the second substrate, the third substrate and a dimming liquid crystal layer positioned between the second substrate and the third substrate; and forming a first polarizer on one side of the third substrate far away from the second substrate. The first polaroid comprises a first metal wire grid polaroid and a transparent protective layer which are sequentially stacked, and the transparent protective layer is positioned on one side, far away from the third substrate, of the first metal wire grid polaroid. In the embodiment of the disclosure, the display device comprising the liquid crystal display panel and the dimming panel is formed by adopting three substrates, so that rainbow lines and water ripples can be reduced while high contrast is realized; the first metal wire grid polaroid is used as a reflection-type polaroid, so that light entering the dimming panel can be reflected for multiple times through the first metal wire grid polaroid, the light transmittance of the dimming panel is improved, and the light transmittance of the display device is further improved; the transparent protective layer arranged in the first polaroid is used as a protective layer in the process of manufacturing and is also used as a protective layer of a final product, so that the thickness of the display device can be reduced by manufacturing the back film, and the light efficiency utilization rate can be increased.

A method for manufacturing a display device and a display device provided in an embodiment of the present disclosure are described below with reference to the accompanying drawings.

Fig. 1 is a partial structural schematic diagram of a display device according to an example of an embodiment of the present disclosure. As shown in fig. 1, a method for manufacturing a display device according to an embodiment of the present disclosure includes stacking a first substrate 100, a second substrate 200, and a third substrate 300 to form a liquid crystal display panel including the first substrate 100, the second substrate 200, and a display liquid crystal layer 400 between the first substrate 100 and the second substrate 200, and a dimming panel including the second substrate 200, the third substrate 300, and a dimming liquid crystal layer 500 between the second substrate 200 and the third substrate 300. That is, the liquid crystal display panel and the dimming panel share the second substrate, and the first substrate, the second substrate, and the third substrate are separate substrates, not substrates formed after being bonded to other substrates, so that the display device forms a double-layer liquid crystal cell using only three substrates.

As shown in fig. 1, the liquid crystal display panel in the embodiment of the present disclosure is used to implement a display function, and the dimming panel is used to control the direction or intensity of the backlight incident to the liquid crystal display panel according to requirements, for example, the dimming panel may implement a requirement of switching between a narrow viewing angle and a wide viewing angle, a requirement of controlling different light intensities at various positions of the liquid crystal display panel, and the like. For example, the backlight may be from a direct-type backlight or a side-type backlight, and light 800 emitted from the backlight passes through a dimming panel and is incident on a liquid crystal display panel to realize display.

In the embodiment of the present disclosure, the display device including the liquid crystal display panel and the dimming panel is formed by using three substrates, so that rainbow lines and moire fringes can be reduced while high contrast is achieved.

For example, the first substrate 100, the second substrate 200, and the third substrate 300 may be a glass substrate, a quartz substrate, or the like, or may be a flexible substrate such as a polyimide substrate for manufacturing a flexible display panel.

As shown in fig. 1, the method for manufacturing a polarizer further includes forming a first polarizer 600 on a side of the third substrate 300 away from the second substrate 200, where the first polarizer 600 includes a Wire-grid polarizer (WGP) 610 and a transparent protection layer, which are sequentially stacked, and the transparent protection layer is located on a side of the first Wire-grid polarizer 610 away from the third substrate 300.

The first metal wire grid polarizer utilizes the oscillation characteristic of free electrons on the surface of metal, so that Transverse Electric (TE) polarized light with the electric field direction parallel to the wire grid direction can excite the electrons to oscillate along the wire grid direction, thereby reflecting; in contrast, Transverse Magnetic (TM) polarized light having an electric field direction perpendicular to the direction of the wire grid cannot excite free electron oscillation due to the limitation of the periodic structure, and therefore TM polarized light mainly exhibits transmission characteristics. That is, the light component with the electric field direction parallel to the wire grid is almost totally reflected by the metal wire grid polarization structure, and conversely, most of the light with the electric field direction perpendicular to the wire grid can transmit through the metal wire grid polarization structure.

The first metal wire grid polarizer in the embodiment of the disclosure is used as a reflection-type polarizer for reflecting light, so that light entering the dimming panel can be reflected for multiple times through the first metal wire grid polarizer, the light transmittance of the dimming panel is improved, and the light transmittance of the display device is further improved.

In the embodiment of the disclosure, the transparent protective layer arranged on one side of the first metal wire grid polarizer, which is far away from the third substrate, is used as a protective layer in the process of manufacturing and is also used as a protective layer of a final product, so that the light efficiency utilization rate can be increased while the thickness of the back film manufactured by thinning the display device is saved.

For example, as shown in fig. 1, according to an example of the embodiment of the present disclosure, before forming the first polarizer 600 on the side of the third substrate 300 away from the second substrate 200, the method includes: forming a dimming cell array 310 at one side of the third substrate 300; the third substrate 300 is then paired with the second substrate 200 at the side where the dimming cell array 310 is formed. That is, before the first polarizer 600 is formed on the third substrate 300, the dimming cell array 310 has been formed on the third substrate 300, and the third substrate 300 on which the dimming cell array 310 is formed is also completed with the second substrate 200.

For example, as shown in fig. 1, the process of cell-aligning the second substrate 200 and the third substrate 300 includes injecting liquid crystal between the second substrate 200 and the third substrate 300 to form the dimming liquid crystal layer 500, and then completing cell-aligning of the second substrate 200 and the third substrate 300 under a vacuum condition to form the dimming panel.

For example, the third substrate 300 becomes a dimming array substrate after forming the dimming cell array 310. The dimming cell array 310 may include a plurality of dimming cells arranged in an array, and each of the dimming cells includes a switching element to control a dimming state of each of the dimming cells. For example, the switching element may include an element such as a Thin Film Transistor (TFT) for driving and controlling the dimming states of the plurality of dimming cells, and the specific structure of the dimming element is not limited in the embodiments of the present disclosure. For example, each dimming cell may further include a dimming electrode for controlling the deflection of liquid crystal molecules in the dimming liquid crystal layer 500, and the dimming electrode is connected to the switching element to control the voltage input to the first dimming electrode, thereby controlling the dimming state of the dimming cell.

For example, the side of the dimming array substrate on which the dimming cell array is formed may be further formed with a plurality of signal lines crossing each other to define a plurality of dimming cells. The signal line may be connected to the first dimming electrode through a switching element to input a voltage to the first dimming electrode.

For example, according to an example of the embodiment of the present disclosure, the first polarizer is separately formed and then transferred and attached to a side of the third substrate away from the second substrate, and the third substrate has been formed as a dimming array substrate before the first polarizer is attached to the third substrate. Since the array substrate is generally formed by a high temperature process (for example, an inorganic film layer such as a gate insulating layer requires a process temperature of about 380 ℃), in this example, by separately preparing the dimming array substrate and the first polarizer and attaching and assembling the dimming array substrate and the first polarizer after the respective preparation is completed, it may not be necessary to consider that the high temperature process of the array substrate affects the characteristics of each film layer in the first polarizer, that is, the manufacturing of the first polarizer is not limited by the manufacturing process of the array substrate. Therefore, the characteristics of the first polarizer can be optimized as much as possible to improve the characteristics of the dimming panel, for example, the transparent protective layer included in the first polarizer can be made of a material with the maximum light transmittance to ensure the light transmittance of the dimming panel.

For example, before the first polarizer is attached to the third substrate, not only the array substrate in the dimming panel but also the array substrate in the liquid crystal display panel are already manufactured, so that the characteristics of the films in the first polarizer are not affected by the manufacturing process of the liquid crystal display panel or the dimming panel.

For example, fig. 2-4 are schematic diagrams illustrating a process of forming a first polarizer in the embodiments of the present disclosure. As shown in fig. 2, the step of forming the first polarizer includes: a mechanical peeling layer 11, transparent

protective layers

620 and 630, a first metal wire grid polarizer 610, a bonding protective layer 640, and a storage protective layer 12 are sequentially formed on a carrier substrate 10 in a stacked arrangement.

For example, the mechanical release layer 11 may be transferred onto the carrier substrate 10 by an APR (ashikasei Photosensitive Resin) transfer method. The APR plate, also called relief plate, is mainly used for roller printing of alignment liquid in processes of twisted nematic panels (TN panels), super twisted nematic panels (STN panels), thin film field effect transistor panels (TFT panels), and the like in the liquid crystal display industry, that is, transferring the alignment liquid onto a glass substrate to form a uniform alignment liquid coating.

The embodiment of the disclosure is not limited thereto, and the mechanical peeling layer 11 may be formed by coating on the carrier substrate 10. In the coating process, the coating material may be baked in an air environment at 100 ℃/2mins or 350 ℃/60mins, or in a nitrogen environment at 500 ℃/10mins, which is not limited in the embodiments of the present disclosure.

For example, a second transparent protective layer 630 is formed on the side of the mechanical peeling layer 11 remote from the carrier substrate 10. For example, the material of the second transparent protection layer 630 is Colorless Polyimide (CPI), the transparency of the second transparent protection layer 630 is greater than 90%, the yellow index (yellowness index) is less than 5, and the thickness is less than 5 μm.

The yellowness index is the degree of deviation from white or yellowing of the polymer material, and can be measured by a yellowness index meter. General Polyimides (PI) have yellow color, which results in insufficient light efficiency, for example, the transparency of general Polyimides (PI) is not more than 85%, and the yellow index is not less than 10.

The CPI is transparent and colorless polyimide, can maintain all characteristics of common PI, is a transparent material, and can play a role in improving the lighting effect when applied to a display device. The embodiment of the disclosure adopts CPI to replace PI, so that the light transmittance of the display device can be effectively improved.

For example, a polyimide material may be coated on the mechanical peeling layer 11. For example, the polyimide material is formed by chemical vapor deposition at a deposition temperature of 60 to 110 ℃, a pressure of 10PA or less, a deposition time of 560 seconds, and then maintained at 350 ℃ for 1 hour.

For example, a fluorine-containing group, an alicyclic structure, a sulfone group, a flexible group, a large side group and a non-coplanar structure are introduced into the molecular structure of polyimide to optimize, and the intramolecular and intermolecular forces are reduced to reduce the formation of a Charge Transfer Complex (CTC), so that a certain orientation structure appears on the surface of the film, and the colorless and transparent polyimide film is prepared.

Since the temperature of the fabrication process for forming the Colorless Polyimide (CPI) and other subsequent fabrication processes in the embodiments of the present disclosure cannot be higher than 350 ℃, it is necessary to avoid the influence of the high temperature process for forming the array substrate in the liquid crystal display panel and the dimming panel on the characteristics of the Colorless Polyimide (CPI). The method for separately manufacturing the first polarizer and each array substrate is adopted, so that the Colorless Polyimide (CPI) in the first polarizer is not limited by the manufacturing process of the array substrate, the waste of the first polarizer process is reduced, the light transmittance of the display device can be better ensured, and the product cost can be reduced.

For example, a first transparent protective layer 620 may be applied to a side of the second transparent protective layer 630 remote from the mechanical release layer 11. For example, the material of the first transparent protection layer 620 may be a transparent material such as silicon oxide or silicon nitride.

For example, a metal layer, such as an aluminum layer, may be formed on the side of the first transparent protection layer 620 away from the second transparent protection layer 630, and then the first wire grid polarizer 610 is fabricated and formed by a method such as nanoimprint or laser direct structuring.

For example, the first transparent protective layer 620 directly contacts one side surface of the first metal wire grid polarizer 610 to protect the first metal wire grid polarizer 610, so that the first metal wire grid polarizer 610 can be prevented from being scratched. In addition, the first transparent protection layer 620 may also have a water and oxygen blocking effect to prevent external moisture from affecting the characteristics of the first metal wire grid polarizer 610.

For example, after the first metal wire grid polarizer 610 is formed, the attachment protection layer 640 is formed on the side of the first metal wire grid polarizer 610 away from the first transparent protection layer 620. For example, the material of the bonding protective layer 640 may be a transparent material such as silicon oxide or silicon nitride. The adhesion protection layer 640 directly contacts the other side surface of the first wire grid polarizer 610 to protect the first wire grid polarizer 610, so that the first wire grid polarizer 610 can be prevented from being scratched. In addition, the adhesion protection layer 640 may also have a water and oxygen blocking effect, so as to prevent external water vapor from affecting the characteristics of the first metal wire grid polarizer 610.

For example, after forming the attachment protection layer 640, the method of separately forming the first polarizer 600 further includes attaching the storage protection layer 12 to the side of the attachment protection layer 640 away from the first wire grid polarizer 610. For example, the material of the storage protection layer 12 may be tetrapropylene fluoride rubber (TPF), and the disclosed embodiments include, but are not limited to, this.

Before the first polaroid is formed independently and transferred to be attached to the third substrate of the dimming panel, the temporary protection effect on the first metal wire grid polaroid and the attachment protection layer can be achieved by forming the storage protection layer on one side, away from the glass substrate, of the first metal wire grid polaroid so as to prevent the attachment protection layer from being damaged.

For example, as shown in FIG. 3, the mechanical release layer 11 and the carrier substrate 10 may need to be removed before the first polarizer 600 is ready to be attached to the third substrate.

In an actual production process, the first polarizer formed in the above process is a mother board with a large size, and the mother board may be subjected to laser cutting to form a plurality of first polarizers for being attached and matched with the third substrates of the plurality of dimming panels.

For example, as shown in fig. 1 and 4, attaching the first polarizer 600 to the third substrate 300 at a side away from the second substrate 200 includes: after removing the storage protection layer 12, the side of the attachment protection layer 640 away from the first wire grid polarizer 610 is attached to the third substrate 300 by a pressure sensitive double-sided adhesive (not shown) or other adhesive layer. After the first polaroid is attached, the second transparent protection layer is used as a back film of the dimming panel to protect the dimming panel.

The first polarizer is an external polarizer of the liquid crystal display panel and the dimming panel, so that the second transparent protective layer is not only used as a protective layer in the process of manufacturing, but also used as a back film of a final product to continuously protect the liquid crystal display panel and the dimming panel. The thickness of the back film in a general display device is 25-120 micrometers, while the thickness of the second transparent protection layer used as the back film in the embodiment of the disclosure is less than 5 micrometers, so that the thickness of the display device can be effectively reduced.

For example, fig. 5 to 6 are schematic diagrams illustrating formation of a first polarizer on a third substrate according to another example of an embodiment of the present disclosure. As shown in fig. 5, the step of forming the first polarizer 600 on the third substrate 300 includes: a first metal wire grid polarizer 610 and transparent

protective layers

620 and 630 are sequentially stacked on one side of the third substrate 300.

For example, as shown in fig. 5, a metal layer, such as an aluminum layer, is formed on the third substrate 300, and then a first metal wire grid polarizer 610 is formed by using a method such as nanoimprint or laser direct structuring. The first metal wire grid polarizer in this example may have the same structure, characteristics and functions as the first metal wire grid polarizer in the examples shown in fig. 1 to 4, and will not be described herein again.

For example, as shown in fig. 5, a first transparent protective layer 620 is formed on a side of the first metal wire grid polarizer 610 away from the third substrate 300. The method for forming the first transparent protection layer 620 and the structure, characteristics and functions of the formed first transparent protection layer 620 in this example are the same as those of the first transparent protection layer in the example shown in fig. 1 to 4, and are not described again here.

For example, as shown in fig. 5, a second transparent protective layer 630 is formed on a side of the first transparent protective layer 620 away from the first wire grid polarizer 610.

The material of the second transparent protection layer 630 in this example is Colorless Polyimide (CPI), the transparency of the second transparent protection layer 630 is greater than 90%, the yellow index (yellowness index) is less than 5, and the thickness is less than 5 μm. In the example, the light transmittance of the display device can be effectively improved by replacing Polyimide (PI) with CPI, the transparency of which is not more than 85% and the yellow index of which is not less than 10. The second transparent protective layer will have the effect of protecting the first metal wire grid polarizer during the manufacturing process.

For example, as shown in fig. 6, the third substrate 300 on which the first polarizer 600 is formed is turned over, and the dimming cell array 310 is formed on the other side of the third substrate 300, that is, the first polarizer 600 and the dimming cell array 310 are formed on the third substrate 300 by a double-sided process.

The method of forming the dimming cell array 310 on the third substrate 300 in this example is different from the example shown in fig. 1 to 4 in that: there is no requirement for the preparation temperature for forming the dimming cell array on the third substrate in the examples shown in fig. 1 to 4, but the process temperature for forming the dimming cell array in the present example is not more than 350 ℃.

Since the first polarizer in the example shown in fig. 1-4 is transferred after being separately formed and attached to the third substrate on which the dimming cell array is formed, the manufacturing process of the first polarizer is not limited by the manufacturing process of the dimming cell array, and the manufacturing process of the dimming cell array is not limited by the manufacturing process of the first polarizer, so that the manufacturing process of the dimming cell array in the example shown in fig. 1-4 can still be a high-temperature process.

In the present example, after the first polarizer is formed on one side of the third substrate, the double-sided process of forming the dimming cell array on the other side of the third substrate needs to take account of the influence of both processes, and since the first polarizer including Colorless Polyimide (CPI) is formed on the third substrate, the temperature of the subsequent preparation process for forming the dimming cell array is required to be not more than 350 ℃, that is, the dimming array substrate is manufactured by using a low-temperature process. In addition, the dimming panel only plays a role of an optical switch, so the dimming array substrate formed by the low-temperature process does not influence the dimming performance of the dimming panel.

In addition, the first polarizer is an external polarizer of the liquid crystal display panel and the dimming panel, so the second transparent protective layer (CPI) is not only used as a protective layer in the process of manufacturing, but also used as a back film of a final product to continuously protect the liquid crystal display panel and the dimming panel. The thickness of the back film in a general display device is 25-120 micrometers, while the thickness of the second transparent protection layer used as the back film in the embodiment of the disclosure is less than 5 micrometers, so that the thickness of the display device can be effectively reduced.

For example, fig. 7 is a schematic diagram of forming a second polarizer on a second substrate according to another example of an embodiment of the present disclosure. As shown in fig. 7, a second polarizer 700 is formed at one side of the second substrate 200. For example, forming the second polarizer 700 includes: a second metal wire grid polarizer 710, a third transparent protection layer 720, a fourth transparent protection layer 730 and a temporary protection layer 21 are sequentially formed on one side of the second substrate 200.

For example, as shown in fig. 7, the step of forming the second polarizer may include forming a metal layer, such as an aluminum layer, on one side of the second substrate 200, and then forming the second metal wire grid polarizer 710 by using a method such as nanoimprint or laser direct structuring.

For example, the polarization direction of polarized light transmitted through the second metal wire grid polarizer 710 shown in fig. 7 is perpendicular to the polarization direction of polarized light transmitted through the first metal wire grid polarizer 610 provided in each of the examples shown in fig. 1-6.

For example, the second metal wire grid polarizer 710 in this example may also be used as a reflective polarizer for reflected light, in which case, light reflected by the second metal wire grid polarizer 710 is depolarized by the first metal wire grid polarizer 610 and then reflected again, and the light undergoes multiple specular reflections between the second metal wire grid polarizer 710 and the first metal wire grid polarizer 610, so that the transmittance of the light is significantly increased.

For example, as shown in fig. 7, a third transparent protection layer 720 is coated and formed on a side of the second metal wire grid polarizer 710 away from the second substrate 200 to protect the second metal wire grid polarizer 710. The third transparent protection layer 720 may have a water and oxygen blocking effect to prevent external moisture from affecting the characteristics of the second metal wire grid polarizer 710.

For example, as shown in fig. 7, a fourth transparent protective layer 730 and a temporary protective layer 21 are sequentially formed on the side of the third transparent protective layer 720 away from the second metal wire grid polarizer 710. The fourth transparent protection layer 730 located between the third transparent protection layer 720 and the temporary protection layer 21 can increase the adhesion of the interface between the two, thereby avoiding the occurrence of abnormalities in the process.

For example, the thickness of the third transparent protection layer 720 is 1000 to 2000 angstroms, the material of the third transparent protection layer 720 may be silicon oxide, the material of the fourth transparent protection layer 730 may be amorphous silicon, and the thickness of the fourth transparent protection layer 730 is 60 to 100 angstroms. For example, the material of the temporary protection layer 21 may be Polyimide (PI).

For example, fig. 8 is a schematic diagram of forming an array of display cells in the example shown in fig. 7. As shown in fig. 8, in the process of forming the second polarizer 700 on one side of the second substrate 200 and then turning the second substrate 200 to form the display cell array 210 on the other side of the second substrate 200, the temporary protection layer 21 serves as a protection layer on the bottom layer and contacts the process base to prevent the process base from scratching the second metal wire grid polarizer. That is, the present example employs a double-sided process to form the second polarizer and the display cell array on both sides of the second substrate, respectively.

For example, the second substrate on which the display cell array is formed is a display array substrate. The display cell array may include a plurality of display cells arranged in an array, and each display cell may include a pixel driving circuit, for example, a structure including a Thin Film Transistor (TFT), a pixel electrode, and the like for driving and controlling a display state of the liquid crystal display panel, and a signal line for supplying a signal to the pixel driving circuit, and the like. The present example can form the structural elements in the above-described display unit using a semiconductor process, and a person skilled in the art can refer to conventional techniques.

As shown in fig. 7 to 8, on one hand, after the second polarizer 700 is formed on the second substrate 200, in the process of turning the second substrate 200 to form the display cell array 210, the temporary protection layer 21 is located at the lowest layer to protect the second wire grid polarizer 710 and prevent the second wire grid polarizer 710 from being scratched. On the other hand, since the temporary protection layer 21 has a high temperature resistant characteristic, a high temperature process in forming the subsequent display cell array 210 does not substantially affect the characteristic of the temporary protection layer 21.

For example, fig. 9 is a schematic diagram of the first substrate and the second substrate facing each other. For example, a color filter layer (not shown) may be formed on one side of the first substrate 100, and the color filter layer may include a plurality of pixel units arranged in an array, each of the plurality of pixel units including a plurality of different color sub-pixels, for example, including a red sub-pixel, a green sub-pixel, and a blue sub-pixel.

For example, an alignment film (not shown) or the like may be formed on the side of the first substrate 100 where the color filter layer is formed, a polarizer (not shown) or the like may be disposed on the side of the first substrate 100 away from the second substrate, and an alignment film (not shown) or the like may be formed on the side of the second substrate 200 where the display cell array 210 is formed. The side of the first substrate 100 provided with the color filter layer is disposed opposite to the side of the second substrate 200 provided with the display cell array 210, and liquid crystal is injected between the first substrate 100 and the second substrate 200 to form a display liquid crystal layer 400, and then cell alignment of the first substrate 100 and the second substrate 200 is completed under a vacuum condition to form a liquid crystal display panel.

For example, fig. 10 is a schematic structural diagram after the temporary protection layer is removed. As shown in fig. 9 to 10, after the first substrate 100 and the second substrate 200 are completed aligned to form the liquid crystal display panel, the liquid crystal display panel is turned over so that the temporary protective layer 21 is positioned at the uppermost layer, and then the temporary protective layer 21 is removed.

For example, the temporary protection layer may be etched using a dry etch to remove the protection layer. For example, the protective layer may be over-etched to completely remove the temporary protective layer, and at this time, the third transparent protective layer 720 may function to sufficiently protect the second wire grid polarizer 710.

For example, fig. 11 is a schematic structural diagram of a dimming panel formed by cell-pairing the second substrate in the liquid crystal display panel shown in fig. 10 and the third substrate in the example shown in fig. 6. As shown in fig. 10 to 11, a side of the second substrate 200 provided with the second polarizer 700 is opposite to a side of the third substrate 300 where the first polarizer 600 is not formed, and liquid crystal is injected between the third substrate 300 and the second substrate 200 to form the dimming liquid crystal layer 500, and then cell alignment of the third substrate 300 and the second substrate 200 is completed under a vacuum condition to form the dimming panel.

For example, in the embodiments of the present disclosure, the size of the display unit in the liquid crystal display panel is smaller than the size of the dimming unit in the dimming panel, that is, one dimming unit corresponds to a plurality of display units, so that not only the dynamic local light control at the pixel level can be implemented, and a better contrast ratio can be obtained, but also no larger power consumption can be generated.

For example, in the embodiments of the present disclosure, the method for forming a liquid crystal display panel provided in the examples shown in fig. 7 to 10 may be applied to the examples shown in fig. 1 to 4 to form a display device, and at this time, the manufacturing process of the independently formed first polarizer is not affected by the manufacturing process of the array substrate in the liquid crystal display panel or the array substrate in the dimming panel, and the characteristics of the first polarizer may be optimized to the maximum.

Of course, the embodiment of the disclosure is not limited to forming the second polarizer by the above-mentioned double-sided process, and an integrated sheet structure may be directly formed on the second substrate instead of the second polarizer with the wire grid structure, and then the second substrate and the third substrate are aligned.

It should be noted that no matter which method is used to form the second polarizer, the process of the liquid crystal display panel and its normal display effect cannot be affected.

Referring to fig. 1 and 11, a display device according to another embodiment of the present disclosure includes a first substrate 100; a second substrate 200 configured to be aligned with the first substrate 100 to form a liquid crystal display panel; a third substrate 300 configured to be aligned with the second substrate 200 to form a dimming panel; the first polarizer 600 is located on a side of the third substrate 300 away from the second substrate 200. The first polarizer 600 includes a first metal wire grid polarizer 610 and a transparent protection layer stacked in sequence, and the transparent protection layer is located on one side of the first metal wire grid polarizer 610 far away from the third substrate 300.

In the embodiment of the disclosure, the display device comprising the liquid crystal display panel and the dimming panel only comprises three substrates, so that rainbow lines and water ripples can be reduced while high contrast is realized; the first metal wire grid polaroid is used as a reflection-type polaroid, so that light entering the dimming panel can be reflected for multiple times through the first metal wire grid polaroid, the light transmittance of the dimming panel is improved, and the light transmittance of the display device is further improved; the transparent protective layer arranged in the first polaroid is used as a protective layer in the process of manufacturing and is also used as a protective layer of a final product, so that the thickness of the display device can be reduced by manufacturing the back film, and the light efficiency utilization rate can be increased.

For example, as shown in fig. 1 and 11, a display device provided in an embodiment of the present disclosure may be a display device formed by using the manufacturing method provided in any one of the examples shown in fig. 1 to 11. The liquid crystal display panel in the embodiment of the present disclosure is used for implementing a display function, and the dimming panel is used for controlling a direction or intensity of backlight incident to the liquid crystal display panel according to a requirement, for example, the dimming panel may implement a requirement for switching between a narrow viewing angle and a wide viewing angle, a requirement for controlling different light intensities at various positions of the liquid crystal display panel, and the like. For example, the backlight may be from a direct-type backlight or a side-type backlight, and light 800 emitted from the backlight passes through a dimming panel and is incident on a liquid crystal display panel to realize display.

For example, as shown in fig. 1 and 11, the transparent protective layer includes a first transparent protective layer 620 in contact with the first wire grid polarizer 610, and a second transparent protective layer 630 positioned at a side of the first transparent protective layer 620 away from the first wire grid polarizer 610.

For example, the material of the first transparent protection layer 620 may be a transparent material such as silicon oxide or silicon nitride.

For example, the material of the second transparent protection layer 630 is Colorless Polyimide (CPI), the transparency of the second transparent protection layer 630 is greater than 90%, the yellow index (yellowness index) is less than 5, and the thickness is less than 5 μm. The embodiment of the disclosure adopts CPI to replace PI, so that the light transmittance of the display device can be effectively improved. In addition, the first polarizer is an external polarizer of the liquid crystal display panel and the dimming panel, so the second transparent protective layer (CPI) is not only used as a protective layer in the process of manufacturing, but also used as a back film of a final product to continuously protect the liquid crystal display panel and the dimming panel. The thickness of the back film in a general display device is 25-120 micrometers, while the thickness of the second transparent protection layer used as the back film in the embodiment of the disclosure is less than 5 micrometers, so that the thickness of the display device can be effectively reduced.

For example, as shown in fig. 1 to 4, the first polarizer 600 further includes a bonding protection layer 640 located on a side of the first metal wire grid polarizer 610 facing the third substrate 300, and a side of the bonding protection layer 640 away from the first metal wire grid polarizer 610 is bonded on the third substrate 300.

For example, the material of the bonding protective layer 640 may be a transparent material such as silicon oxide or silicon nitride. The adhesion protection layer 640 directly contacts the other side surface of the first wire grid polarizer 610 to protect the first wire grid polarizer 610, so that the first wire grid polarizer 610 can be prevented from being scratched. In addition, the adhesion protection layer 640 may also have a water and oxygen blocking effect, so as to prevent external water vapor from affecting the characteristics of the first metal wire grid polarizer 610.

For example, a second polarizer 700 is disposed on a side of the second substrate 200 facing the third substrate 300, the second polarizer 700 includes a second metal wire grid polarizer 710, a third transparent protective layer 720 and a fourth transparent protective layer 730 sequentially disposed on the second substrate 200, and the second metal wire grid polarizer 710 is disposed between the third transparent protective layer 720 and the second substrate 200. The third transparent protective layer 720 may protect the second metal wire grid polarizer 710. The third transparent protection layer 720 may have a water and oxygen blocking effect to prevent external moisture from affecting the characteristics of the second metal wire grid polarizer 710.

For example, the thickness of the third transparent protection layer 720 is 1000 to 2000 angstroms, and the thickness of the fourth transparent protection layer 730 is 60 to 100 angstroms.

For example, the polarization direction of the polarized light transmitted by the second metal wire grid polarizer 710 is perpendicular to the polarization direction of the polarized light transmitted by the first metal wire grid polarizer 610.

For example, the second metal wire grid polarizer 710 may also be used as a reflective polarizer for reflected light, in which case, light reflected by the second metal wire grid polarizer 710 is depolarized by the first metal wire grid polarizer 610 and then reflected again, and the light is reflected by multiple mirror reflections between the second metal wire grid polarizer 710 and the first metal wire grid polarizer 610, so that the transmittance of the light is significantly increased.

For example, the display device provided by the embodiment of the disclosure can be a large-sized display device such as a television, an electronic picture frame, and the like. Of course, the embodiments of the present disclosure include but are not limited thereto, and the display device may also be an electronic product with a display function, such as a computer, a notebook computer, a mobile phone, a tablet computer, and a navigator.

The following points need to be explained:

(1) in the drawings of the embodiments of the present disclosure, only the structures related to the embodiments of the present disclosure are referred to, and other structures may refer to general designs.

(2) Features of the same embodiment of the disclosure and of different embodiments may be combined with each other without conflict.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present disclosure, and all the changes or substitutions should be covered within the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

A method for manufacturing a display device includes:

sequentially stacking a first substrate, a second substrate and a third substrate to form a liquid crystal display panel and a dimming panel, wherein the liquid crystal display panel comprises the first substrate, the second substrate and a display liquid crystal layer positioned between the first substrate and the second substrate, and the dimming panel comprises the second substrate, the third substrate and a dimming liquid crystal layer positioned between the second substrate and the third substrate;

a first polarizer is formed on one side of the third substrate far away from the second substrate,

the first polaroid comprises a first metal wire grid polaroid and a transparent protective layer which are sequentially stacked, and the transparent protective layer is located on one side, away from the third substrate, of the first metal wire grid polaroid.
The manufacturing method according to claim 1, wherein before forming the first polarizer on a side of the third substrate away from the second substrate, the method comprises:

forming a dimming cell array on one side of the third substrate;

aligning the third substrate with the side of the dimming cell array and the second substrate to form the dimming panel,

the forming of the first polarizer on the side of the third substrate away from the second substrate includes:

and forming the first polaroid, and transferring and attaching the first polaroid to one side of the third substrate, which is far away from the second substrate.
The manufacturing method according to claim 2, wherein forming the first polarizer comprises: sequentially forming a mechanical stripping layer, the transparent protective layer, the first metal wire grid polarizer, a bonding protective layer and a storage protective layer which are arranged in a laminated manner on a bearing substrate;

transferring and attaching the first polarizer to one side of the third substrate far away from the second substrate comprises the following steps: and after removing the mechanical stripping layer, the bearing substrate and the storage protective layer, attaching one side of the attaching protective layer, which is far away from the first metal wire grid polarizer, to the third substrate.
The manufacturing method according to claim 1, wherein the forming of the first polarizer on the side of the third substrate away from the second substrate comprises: sequentially forming the first metal wire grid polarizer and the transparent protective layer laminated on one side of the third substrate to form the first polarizer,

the method comprises the following steps of after forming a first polarizer on one side of the third substrate far away from the second substrate: forming a dimming cell array on the other side of the third substrate, wherein the process temperature for forming the dimming cell array is not more than 350 ℃;

and aligning the third substrate with the side of the dimming cell array and the second substrate to form the dimming panel.
The method of making as defined in claims 1-4, wherein the transparent protective layer includes a first transparent protective layer in contact with the first wire grid polarizer and a second transparent protective layer on a side of the first transparent protective layer away from the first wire grid polarizer.
The manufacturing method according to claim 5, wherein the material of the second transparent protective layer is colorless polyimide, the transparency of the second transparent protective layer is greater than 90%, the yellow index is less than 5, the thickness is less than 5 μm, and the second transparent protective layer is configured as a back film of the dimming panel.
The manufacturing method according to any one of claims 1 to 6, wherein forming the liquid crystal display panel comprises:

forming a second polarizer on one side of the second substrate;

after the second polarizer is formed, forming a display unit array on the other side of the second substrate, wherein forming the liquid crystal display panel includes: and aligning one side of the second substrate, on which the display unit array is formed, with the first substrate.
The manufacturing method according to claim 7, wherein the forming of the second polarizer comprises sequentially forming a second metal wire grid polarizer, a third transparent protective layer, a fourth transparent protective layer and a temporary protective layer on the second substrate;

the step of aligning the side of the second substrate on which the display unit array is formed with the first substrate includes: removing the temporary protection layer;

and the side of the second substrate, on which the second polarizer is formed, is paired with the third substrate to form the dimming panel.
The manufacturing method of claim 8, wherein the third transparent protective layer is made of silicon oxide, and the thickness of the third transparent protective layer is 1000-2000 angstroms; the fourth transparent protection layer is made of amorphous silicon, and the thickness of the fourth transparent protection layer is 60-100 angstroms.
A display device, comprising:

a first substrate;

a second substrate configured to be aligned with the first substrate to form a liquid crystal display panel;

a third substrate configured to be aligned with the second substrate to form a dimming panel;

a first polarizer located on one side of the third substrate far away from the second substrate,

the first polaroid comprises a first metal wire grid polaroid and a transparent protective layer which are sequentially stacked, and the transparent protective layer is located on one side, far away from the third substrate, of the first metal wire grid polaroid.
A display device according to claim 10, wherein the transparent protective layer comprises a first transparent protective layer in contact with the first wire grid polarizer and a second transparent protective layer on a side of the first transparent protective layer remote from the first wire grid polarizer.
The display device of claim 11, wherein the material of the second transparent protective layer is a colorless polyimide, the second transparent protective layer has a transparency greater than 90%, a yellowness index less than 5, and a thickness less than 5 micrometers, and is configured as a back film of the dimming panel.
The display device according to any one of claims 10 to 12, wherein the first polarizer further comprises a conformable protective layer on a side of the first wire grid polarizer facing the third substrate, and a side of the conformable protective layer away from the first wire grid polarizer is conformed to the third substrate.
The display device according to claim 13, wherein a side of the second substrate facing the third substrate is provided with a second polarizer, the second polarizer comprising a second metal wire grid polarizer, a third transparent protective layer, and a fourth transparent protective layer in this order on the second substrate, the second metal wire grid polarizer being between the third transparent protective layer and the second substrate.
The display device according to claim 14, wherein the third transparent protective layer is made of silicon oxide, and has a thickness of 1000 to 2000 angstroms; the fourth transparent protection layer is made of amorphous silicon, and the thickness of the third transparent protection layer is 60-100 angstroms.